I have an iPhone 5S running 7.0.4 Jailbroken (evasi0n 7.x) I've got the cydia source as well as AppSync installed for iOS 7. When I slide to install on the website it asks if I'd like to install so I click yes, it looks like it downloads fine because the circle goes around on the app, but then it stops and the whole app goes dark. I've tried reinstalling AppSync for iOS 7.0+ (from app.appaddict.org) and AA itself from the AppAddict.org with Safari and also on a "Safe Mode" too .. and nothing seems to work. Is it a problem with appaddict or am I just doing something wrong?
as Zorror said, our AppSync is working with Substrate, if you're trying in SafeMode, it won't work,
but anyways why you try install it in safe mode ? your issue won't solve in that way !!!!
try find out you are able to install other cracked apps or not